Nurture surpasses nature: The intergenerational transmission of depression from African mothers to their adolescent children

Abstract:

Mental health in South Africa has been neglected as a public health and policy issue, particularly
among adolescents. This is unfortunate, as nineteen percent of African adolescents in South Africa
suffered from depression in 2014, and these rates were even higher for adolescents with mothers
with poor mental health. Previous work has estimated the impact of parental depression on child
depression in South Africa, and found it to be substantial, particularly for adolescent children. A
teenager whose mother suffers from depression will have a risk of depression which is thirty
percentage points higher than teens whose mothers do not suffer from depression. In order to decide
on the best method of treatment to prevent transmission from occurring, it is necessary to disentangle
the effect into its environmental and genetic components. There is no similar literature on this
relationship in the South African context. This paper investigates the nature of depression
transmission to African adolescents in South Africa, and finds that it is primarily environmental factors
which account for the transmission of depression to children. Using a variety of techniques, we find
that once the “nurture” effect has been accounted for, the “nature” effect is negligible. This implies
that mitigating negative factors in a household, and in communities, as opposed to directly treating
adolescent mental health using conventional approaches, may be the best approach, particularly in a
country struggling with a lack of mental health professionals.